Apparatus for producing electric sparks.



W. MARSHALL. APPARATUS FOR PRODUCING ELECTRIC SPARKS.

APPLICATION FILED 0OT,29,-1906.

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WWW ZWMA, WWMNXWf WK W gW/WV QTM W FW I f y PATENTED JUNE 25, 1907.

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WILLIAM MARSHALL, OF I 1W YORK, N. Y., ASSIGNOR )F ONE-FOURTH TO JOHN A. BULLINGER, OF NEW YORK, N. Y.

APPARATUS FOR PRODUCING EL ECTRIC SPARKS.

Specification of Letters Patent.

Patented June 25, 1907.

Original application filed lay 2, 1906, fierial No. 314,765. Divided and this application filed October 29,1906. Serial No. 340,966-

To all whont it Wtay concern:

Be it known that I, WILLIAM. MARsHALL, a

citizen of the United States, and a resident of the borough of Manhattan, city, county, and

State of New York, have invented certain. new and useful Improvements in Apparatus for Producing Electric Sparks, of which the following is a specification.

My invention relates to apparatus for producing oscillating electric discharges or s arks for various urposes wlieresuch dis- 0 arges may be uti ized, as for theignition of the explosive mixture in internal combustion engines, for lighting gas burners, and for producing electric or similar waves for wireused in connection t erewith; and Fig. 3 is an end-view of such spark-plug.

\ I may employ any suitable source-of electricity, such as a battery A, and with the poles thereof are connected, in parallel, the primary coils B, B, like poles of the battery being connected with like terminals of the coils, at least this is the connection I believe to be preferable. Of course, the same result could be obtained by havin a separate battery for each coil, but t e arrangement shown is preferred. Each of the primary coil circuits includes an interrupter of any approved character, the well-known electric vibrator being indicated at C, C. Wound. ininductive relation to the primary coils B, B, are the secondary coils D, D respectively. With the terminals of these secondary coils are connected three wires, E, E E one of which, E, is connected with like terminals of both coils D, D, while each of the other wires is connected with one of the remaining terminals of the secondary coils. Two spark aps F, F, are thus formed, the ends of the three wires being placedtogether close enough for sparks to pass from the wire E to both wires,'E, E when induced currents are produced in'the secondary coils D, D by the closing and interruption of the primary coil circuits. The best results are produced, apparently, when the interrupters work synchronously, and this can be ascortained with fair accuracy, when the ordinary vibrators are employed, by adjusting them until both emit a sound of the same pitch.

The s arksproduced with my arrangement as speci ed in the claims are longer and particularly more frequent, brighter and fatter than could be obtained otherwise from the' same coils and the same battery. The circuit arrangement is therefore very valuable for the electric ignition of gas engines, gasolene engines and the like, but may be employed wherever electric sparks or oscillating discharges are to be produced, as for lighting gas burners and in wireless telegraphy.

When applying my invention to internal combustion engines, I may give the sparkplug the particular construction shown in 1g. 2. to fit the customary opening in the cylinder or cylinder-head. Into this is fitted a sleeve H of insulating material, such as porcelain or mica, which surrounds a metal sleeve J adapted to' form the secondelectrode. Within this electrode is another insulator K through which extends the central electrode L. The inner edges, of the bodyG and f the sleeve J should preferably be in about the same plane with the end of the central electrode L. The sleeve electrode J would be connected with the wire E, the central electrode L eitherwith the wire E or the Wire E and the frame of the machine, and therefore the body G, with the third Wire. This spark-plug is very efficient not only on account of the superior character of the spark, but owing to the fact that the sparks will be distributed over a much larger area, thus igniting'the mixture at various points. The two spark gaps are of the same width, or substantially so.

Various modifications may be made with out departing fromthe nature of my inven tion as set forth in the appended claims.

Thus it obviousl is immaterial whether the secondary coils, D, are really two separate coils, or whether they simply constitute the halves of a single secondary 0011, the wire G is the metal body screw-threaded I E being connected with the central portion of such coil.

This'application is a division of another application. filed by me in the United States Patent Office on May 2, '1906, Serial No.

314,7 65, in which the park plug herein-described is claimed:

I claim:

1. An electric ,oscillator comprising a source of electricity, two primary coils connected therewith in parallel, an interrupter in the circuit of each coil, a secondary coil in inductive relation to each primary, a conductor connected with like terminals of both secondaries, and two additional conductors each connected wlth one of the remaining terminals, said conductors having portions arranged adjacent to each other to produce spark gaps.

2. An electric oscillator comprising a source of electricity, two primary coils connected therewith in parallel, an interrupter in the circuit of each coil, a secondary 0011 in inductive relation to each primary, a conductor connected with one terminal of each secondary, and two additional conductors each connected with one of the remaining termlnals, said conductors having portlons arranged adjacent to each other to produce sparkgaps.

3. An electric oscillator comprising two primary coils, means for interrupting the current, two secondary coils in inductive relation to said primary coils, a conductor connected with liketerminals of both secondaries, and two additional conductors connected with the remaining terminals, said 0011- ductors having portions arranged adjacent to each other to produce spark gaps.

4. An electric oscillator comprising two primary coils, means for interru ting the current, two secondary coils in in uctive relation to said primary coils, a conductor connected with one terminal of each secondary, and two additional conductors each con nected with one of the remaining terminals, said conductors having portion arranged adj acent to each other to produce spark gaps.

In testimony whereof, I have hereunto signed my name in the presence of'two subscribing witnesses.

WILLIAM MARSHALL.

WVitnesses 1 OTTo v. SCHRENK, JOHN A. KEHLENBECK. 

